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142.
张光洁 《湖南环境生物职业技术学院学报》2002,8(1):31-34
分析了衡阳市动物疫情现状,探讨了影响动物疫病发生的社会因素、人为因素和客观因素,结合衡阳市的具体情况,提出了与国际接轨的动物防治目标和对策.着重从政策、法律、经济、技术等方面阐述如何搞好动物防疫工作,提出了搞好动物防疫工作的重要性. 相似文献
143.
144.
南京市城郊蔬菜生产基地有机氯农药残留特征 总被引:4,自引:1,他引:4
以网格法在南京市无公害蔬菜生产基地八卦洲采集70个土壤样品,用加速溶剂萃取、固相萃取柱净化后GC-μECD测定土壤中有机氯农药(α-HCH,β-HCH,γ-HCH和δ-HCH以及o,p'-DDT,p,p'-DDT,o,p'-DDE,p,p'-DDE 和p,p'-DDD)残留量.结果表明,土壤中有机氯农药残留总量在6.18~84.72 μg·kg-1之间,平均18.63 μg·kg-1.DDT残留量高于HCH,为3.36~74.19 μg·kg-1,平均12.61 μg·kg-1.土壤中HCH残留量为2.48~17.80 μg·kg-1,平均6.02 μg·kg-1.DDT同系物中以p,p'-DDE和p,p'-DDT为主,而HCH中δ-HCH含量较低,其他3种异构体含量水平相当.所有土样中DDT和HCH残留量均远远低于GB/T 18407 无公害蔬菜产地土壤标准限定值500 μg·kg-1,但大多数土样中DDT和HCH残留量远远高于荷兰无污染土壤标准. 相似文献
145.
AbstractContaminated food chain is a serious contender for arsenic (As) uptake around the globe. In Nadia, West Bengal, we trace possible means of transfer of As from multiple sources reaching different trophic levels, and associated seasonal variability leading to chronic As uptake. This work considers possible sources-pathways of As transfer through food chain in rural community. Arsenic concentration in groundwater, soil, rice, and vegetable-samples collected detected in different harvest seasons of 2014 and 2016. Arsenic level in shallow groundwater samples ranged from 0.1 to 354?µg/L, with 75% of the sites above the prescribed limit by WHO (10?µg/L) during the boro harvest season. High soil As content (~20.6?mg/kg), resulted in accumulation of As in food crops. A positive correlation in As conc. with increase over period in all sites indicating gradual As accumulation in topsoil. Unpolished rice samples showed high As content (~1.75?mg/kg), polishing reduced 80% of As. Among vegetables, the plant family Poaceae with high irrigation requirements and Solanaceae retaining high moisture, have the highest levels of As. Contaminated animal fodder (Poaceae) and turf water for cattle are shown to contaminate milk (0.06 to 0.24?µg/L) and behoves strategies, practices to minimize As exposure. 相似文献
146.
芜湖市郊土壤污染对土壤动物群落结构的影响 总被引:8,自引:0,他引:8
研究表明,芜湖市郊农田土壤动物群落的组成与数量随污染程度的加重而减少,土壤动物密度也呈同样的变化趋势,特别是中小型土壤动物,优势类群数量发生较大消长,常见类群和稀有类群的组成逐渐减少.多样性指数H与重金属污染程度之间关系因受到季节的影响而变得复杂:冬季和初夏污染较重样地优势类群数量减少,群落均匀性指数E增加而优势度指数C减小,多样性指数H较高;而春季处于过渡阶段,某些类群(如螨类)数量爆发,C增高,H较小.土壤动物群落密度一类群指数DG随污染加重而减小.受到重金属污染的农田土壤动物的表聚性减弱,甚至出现逆分布现象.图1表4参15 相似文献
147.
铜陵市铜尾矿土壤动物群落生态研究 总被引:10,自引:2,他引:10
对安徽省铜陵市铜尾矿地6种生境中土壤动物群落进行野外调查和室内分析,研究不同弃置堆放时间的铜尾矿地土壤的动物群落结构及其与尾矿基质理化性质、植被状况等生境条件之间的关系。结果表明,尾矿堆放时间、区位地貌和植被状况的不同,尾矿基质的理化性质发生变化,导致土壤动物的种类组成和数量分布具有明显差异。土壤动物在土体中的表聚性强,绝大部分集中分布于A层(0~5cm);土壤的物理性质越稳定,土壤动物越丰富;土壤肥力越高,土壤动物越丰富多样。即尾矿地土壤的生境条件越优越,土壤动物群落的物种丰富度越大,个体数量分布越多,群落多样性越高。这些研究结论为尾矿区的生态修复和可持续利用提供了参考依据。 相似文献
148.
Philippa Howell 《Disasters》1998,22(1):57-75
This case study of an NGO's response to a food crisis due to crop failure focuses on the extent of active community participation at each stage of the project. With the current debate on the relationship between relief and development, and in particular the focus on encouraging more active community participation in relief responses, this study has relevance both in the Ethiopian context and beyond.
In this example the participation process was greatly facilitated by the prior relationship between the international NGO and the communities, and also by the high level of staff input into the project. Where resources or conditions are less favourable, as might be the case in similar responses by local NGOs or government agencies, the paper suggests that the participatory approach can be adapted or partially implemented and still result in a more effective and locally relevant operation. 相似文献
In this example the participation process was greatly facilitated by the prior relationship between the international NGO and the communities, and also by the high level of staff input into the project. Where resources or conditions are less favourable, as might be the case in similar responses by local NGOs or government agencies, the paper suggests that the participatory approach can be adapted or partially implemented and still result in a more effective and locally relevant operation. 相似文献
149.
Lantz Miller 《Journal of Agricultural and Environmental Ethics》1998,11(1):1-16
A critique is made of Bernard Rollin's examination of the ethics of cloning adult mammalian cells. The primary concern is less to propound an anticloning or procloning position than to call for full exploration of the ethical complexities before a rush to judgment is made. Indeed, the ethical examination in question rushes toward an ethical position in such a way that does not appear consistent with Rollin's usual methodology. By extending this methodology – which entails full weighing of benefits and costs – it becomes apparent that there are real potential risks to this type of cloning in both animals and humans, besides the possible benefits, and that the scientific, political, philosophical, and broader academic communities should explore these risks and benefits extensively. Rollin's usual methodological call for hesitation before risks would translate into hesitation before the ethical risks of adult mammalian cell cloning instead of his paper's curiously laissez-faire stance. 相似文献
150.